Method for producing a mechanical locking system for building panels

ABSTRACT

Building panels provided with a mechanical locking system including a tongue, at first edge of a first building panel, cooperating with a tongue groove, at a second edge of an adjacent second building panel, for vertical locking of the building panels and a method for producing such building panels. The method includes the step of forming the tongue of material of the first edge. The insertion groove may have a sidewall at a third edge, which is adjacent the first edge, and may be open at a fourth edge, which is opposite the third edge.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.14/946,066, filed on Nov. 19, 2015, which is a continuation of U.S.application Ser. No. 13/855,979, filed on Apr. 3, 2013, now U.S. Pat.No. 9,216,541, which claims the benefit of U.S. Provisional ApplicationNo. 61/620,246, filed on Apr. 4, 2012. The entire contents of U.S.application Ser. No. 14/946,066, U.S. application Ser. No. 13/855,979,U.S. Provisional Application No. 61/620,246 are hereby incorporatedherein by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to a building panel such as a floorpanel, a wall panel, a ceiling panel, a furniture component or the like,which is provided with a mechanical locking system, and a method forproducing said building panel with said locking system.

TECHNICAL BACKGROUND

Building panels provided with a mechanical locking system comprising adisplaceable and resilient tongue cooperating with a tongue groove forvertical locking is known and disclosed in, e.g., WO 2006/043893. Thetongue is a separate part and is made of, e.g., plastic, and positionedin an insertion groove at an edge of a panel. The tongue is pushed intothe insertion groove during a vertical assembling of the panels andsprings back into the tongue groove of an adjacent panel when the panelshave reached a locked position.

Also known is a locking system for panels comprising a tongue, which isslightly longer than the width of a panel, see, e.g., WO 2008/004960,and cooperates with a tongue groove for vertical locking. The tongue isa separate part and is inserted in a displacement groove. The panels maybe assembled by a vertical movement and the tongue is pressed betweenlong edges of two adjacent panels and bent along its length direction.

Although the description relates to floor panel, the description oftechniques and problems thereof is applicable also for otherapplications, such as panels for other purposes, for example wallpanels, ceiling panels, furniture etc.

A drawback with the known system is that a separate tongue must beproduced and special inserting machines are required to position thetongue in the insertion groove with high precision.

The above description of various known aspects is the applicant'scharacterization of such, and is not an admission that any of the abovedescription is considered as prior art.

SUMMARY

It is an object of certain embodiments of the present disclosure toprovide an improvement over the above described techniques and knownart.

A further object is to provide a locking system and a method to producea locking system, which comprises a tongue that may be formed out of theedge of the building panel. Such a system simplifies the productionsince no loose and additional parts are necessary to produce and toposition at the correct position in the locking system.

Another object is to provide a more efficient production method, whichrequires a less complicated production equipment.

At least some of these and other objects and advantages that will beapparent from the description have been achieved by a method forproducing a locking system at edges of building panels. The lockingsystem may comprise a tongue, at first edge of a first building panel,cooperating with a tongue groove, at a second edge of an adjacent secondbuilding panel, for vertical locking of the building panels. The method,which is a first aspect of the disclosure, may comprise the steps of:

-   -   forming material of the first edge to obtain at least parts of        the outer shape of the tongue;    -   forming an insertion groove at the first edge, wherein said        insertion groove is sidewardly open and extends in the        horizontal direction; and    -   displacing the tongue at least partly into the insertion groove.

The forming of the insertion groove and the tongue is preferably made ina production line comprising mechanical cutting devices, such as millingtools. The displacement of the tongue into the insertion groove ispreferably made in the same production line. The tongue may be displacedby a device, which in a first step displaces the tongue in a verticaldirection and in a second step displaces the tongue in a horizontaldirection and into the insertion groove.

The parts of the outer shape of the tongue may be formed at an upperpart of the first edge, preferably above the insertion groove.

The insertion groove may be formed below the upper part of the firstedge and the tongue may be displaced downwards and into the insertiongroove.

The method may furthermore comprise the step of forming a connectionpart between the tongue and an upper edge of the first edge.

The method may comprise the step of forming a connection part by forminga groove between an upper edge of the first edge and outer parts of thetongue. The connection part may have the advantage that the tongue is infixed position until the tongue is displaced.

The method may comprise the step of breaking the connection part by thedisplacement of the tongue. The connection part may also be cut off,preferably in connection with the displacement of the tongue.

The method may comprise the step of forming the tongue groove, at thesecond edge.

An inner groove may be formed throughout the tongue, between the tongueand the first edge of the building panel, in order to obtain a resilienttongue part. The inner groove may extend in the longitudinal directionof the tongue and between a first and a second protruding part of thetongue, at the third and the fourth edge of the building panelrespectively. The resilient tongue part may extend from the first to thesecond protruding part. Before the tongue is displaced into theinsertion groove the protruding parts may function as connection partsas described above.

The method may comprise the step of forming a sidewall in the insertiongroove at a third edge of the first building panel, which is adjacentthe first edge, and forming an opening of the insertion groove at afourth edge at, which is opposite the third edge and adjacent the firstedge. The tongue may be displaced to a position in which a pressing partof the tongue protrudes through the opening of the insertion groove.This position has also a displacement of the tongue in a direction alongthe first edge of the building panel.

The tongue may, in a locked position of the first and second edge, bepressed between the sidewall and an edge of an adjacent building panel,such that the tongue bends and a part of the tongue is pushed into thetongue groove.

The tongue may essentially have the same length as the length of thefirst edge.

The method may comprise the step of forming a locking element at thefirst edge and a locking groove at the second edge or a locking elementat the second edge and a locking groove at the first edge, wherein saidlocking element and locking groove are configured to cooperate forlocking of the first and the second edge in the horizontal direction.

The production steps above may be performed in any order. The buildingpanel may also be positioned upside down in the production line.

The locking system is preferably formed by mechanical cutting, such asmilling, drilling, cutting by knife and/or sawing, of the edges of thebuilding panels.

A second aspect of the disclosure is building panels, which preferablyare produced according to an embodiment of the first aspect, providedwith a mechanical locking system. The locking system may comprise atongue, at first edge of a first building panel, cooperating with atongue groove, at a second edge of an adjacent second building panel,for vertical locking of the building panels. The tongue is preferablyproduced of material of the first edge. The tongue may be at leastpartly positioned in an insertion groove at the first edge.

The tongue may be displaceable in the insertion groove to enable avertical assembling of the first and the second edge. An embodiment mayhave a resilient part between the displaceable tongue and a bottom wallof the insertion groove. The resilient part makes it possible to pushthe displaceable tongue into insertion groove, by an edge of the secondedge, during a vertical assembling of the first and the second edge. Thetongue springs back and into the tongue groove when the first and thesecond building panel have reached a locked position. The embodimentwith the resilient part is particularly useful for building panels withedges comprising a rigid material, such as solid wood. A resilient partmay not be necessary for building panels with edges comprising aresilient material, such as plastic and vinyl. For such building panelsit may be possible to configure a tongue, which is compressible enoughto be pushed into insertion groove during the vertical assembling.

The displaceable tongue may, in another embodiment, be configured suchthat when pressed between a sidewall in the insertion groove and an edgeof an adjacent third building panel the tongue bends and a part of thetongue is pushed into the tongue groove. This solution is particularlyuseful for building panels with edges comprising wood, such as HDF orMDF.

The sidewall may be arranged in the insertion groove at a third edge ofthe first building panel, which is adjacent the first edge and theinsertion groove may have an opening at a fourth edge, which is oppositethe third edge and adjacent the first edge. The displaceable tongue maybe positioned such that a press part of the displaceable tongueprotrudes through the opening. Such a position improves thepossibilities to apply a force on the press part.

Another embodiment comprises a fixed tongue, which preferably isarranged firmly in the insertion groove. The fixed tongue comprises aprotruding part, which protrudes outside the upper edge of the firstedge and cooperates with the tongue groove for the vertical locking. Afirst and a second edge provided with a locking system comprising thefixed tongue may be assembled by an angular movement. This embodiment isparticularly advantageous for thin building panels, preferably with athickness in the range of about 3-7 mm or more preferably in the rangeof about 4-6 mm. A reason is that it's easier to produce a lockingsystem, which comprises a displaceable tongue, at the edge of a thickerbuilding panel than at the edge of a thinner building panel. The toolsfor forming a locking system with a displaceable tongue require morespace and material than the tools for forming a locking system with afixed tongue. This embodiment is particularly useful for plastic andvinyl tiles, which normally have a thin thickness.

Embodiments of the locking system and the building panels in the abovefirst and the second aspect may comprise the features described below.

A contact surface of the tongue groove may cooperate, for the verticallocking, with a contact surface of the tongue.

The contact surface may be positioned such that when the displaceabletongue springs back and into the tongue groove, during a verticalassembling of the building panels, the tongue is prevented to reach itsoriginal position. The contact surface of the tongue asserts a forceagainst the contact surface of the tongue groove in order to avoid aplay between the panels.

The contact surface may be positioned such that when the displaceabletongue is pushed into the tongue groove the contact surface of thetongue asserts a force against the contact surface of the tongue groovein order to avoid a play between the panels.

The locking system may comprise a locking element, preferably arrangedon a locking strip, at the first edge of the first panel and a lockinggroove at the second edge of the second panel or locking groove at thefirst edge of the first panel and a locking element at the second edgeof the second panel. Said locking element and locking groove cooperate,for locking the panels horizontally.

The first and the second building panel are preferably essentiallyequal, thus an edge opposite said first edge of the first panel isprovided with the same parts of the locking system as said second edgeof the second panel.

The panels may be square-shaped and the edges between said first andsaid opposite edge are preferably provided with a locking system, whichenables assembling to an adjacent panel by an angling movement.

The insertion groove may be filled with a resilient material or part,such as plastic or rubber, to improve the resilient properties of thedisplaceable part and/or to make the locking system stronger.

The building panel may be a floor panel, a wall panel, a ceiling panel,a furniture component or the like.

The core of the building panels may be a wood-based core, preferablymade of MDF, HDF, OSB, WPC, or particleboard or of plastic, e.g., vinylor PVC.

The edge of the panels, of which the locking system may be made, maycomprise the core material.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will by way of example be described in moredetail with reference to the appended schematic drawings, which showsembodiments of the present disclosure.

FIG. 1 shows a known locking system with a separate and resilienttongue.

FIGS. 2A-C show a known locking system with a separate and displaceabletongue.

FIGS. 3A-C show cross-sections of known locking systems with a separateand displaceable tongue.

FIGS. 4A-F show cross-sections and top views of known locking systemswith a separate and displaceable tongue.

FIGS. 5A-C show an embodiment of the building panels.

FIGS. 6A-C show top views of an embodiment of the building panels.

FIGS. 7a-c shows an embodiment of an assembling of an embodiment of thebuilding panels.

FIGS. 8A-C shows an embodiment of an assembling of an embodiment of thebuilding panels.

FIGS. 9A-C show top views of an embodiment of the building panels.

DETAILED DESCRIPTION

A known locking system for building panels, which comprises adisplaceable and resilient tongue 30, at a first edge 4 a of a firstpanel 1, cooperating with a tongue groove 20, at a second edge 4 b of asecond panel 1′, for vertical locking of the first and a second edge 4a, 4 b, is shown in FIG. 1. The tongue 30 is a separate part and is madeof, e.g., plastic, and is arranged in an insertion groove at the firstedge 4 a. The tongue 30 is pushed into the insertion groove during avertical assembling of the short edges 4 a, 4 b of the panels andsprings back into the tongue groove 20, when the panels have reached alocked position. The locking system comprises at the first edge alocking strip 8 with a protruding locking element 6, which cooperateswith a locking groove 14 at the second edge. A third and a fourth edge 5a, 5 b of the panels 1′, 1′, 1″ are provided with a locking system,which enables assembling to of panels in a first and second row R1, R2by an angling movement, to obtain a simultaneous locking of adjacentedges 5 a, 5 b, 4 a, 4 b.

FIGS. 2a-c show simultaneously assembling of adjacent long and shortedges 5 a, 5 b, 4 a, 4 b in three steps from FIG. 2a to FIG. 2c . Thesecond panel 1′ is angled down along its first long edge 5 a, at asecond long edge 5 b of a third panel 1″, and the second edge 4 b of thesecond panel 1′ is simultaneous lowered vertically to be connected tothe first edge 4 a of the first panel 1. The tongue 30 is graduallypushed into the insertion groove, see FIG. 2b , and spring back into thetongue groove 20 when the first, the second and the third panels 1, 1′,1″ have reached a locked position, see FIG. 2 c.

FIGS. 3a-c show cross sections of different embodiments of the knowndisplaceable and resilient tongue 30 during assembling of two adjacentshort edges. The panel with the tongue groove is lowered in relation tothe panel with tongue 30, which is pushed into the insertion groove 40by the lowered panel. The tongue springs back, and into the tonguegroove, when the panels has reached a locked position, and locks thepanels vertically.

FIGS. 4a-f discloses another known embodiment, comprising a displaceableand resilient tongue 30, during assembling of a first and a second edge4 a, 4 b of a first and a second panels 1, 1′. This embodiment issimilar to the locking system shown in FIGS. 1-3, but the displaceableand resilient tongue 30 that locks automatically by a spring effectduring the vertical movement is replaced by a displaceable and resilienttongue 30 that locks the first and the second edge 4 a, 4 b, when athird 1″ and a forth 1′″ building panel are assembled at the third andthe forth edge respectively of the first panel 1. The displaceable andresilient tongue 30 is, in this embodiment, longer than the width of thefront face of the first and the second panel 1, 1′. A third and fourthedge 5 a, 5 b of the third and fourth building panel 1″, 1′″respectively, apply a force at outer parts E1, E2 of the displaceableand resilient tongue 30. The force bends the displaceable and resilienttongue 30 and a part is pushed into the tongue groove 20 at the secondedge of the second panel 1′.

Embodiments of the disclosure are shown in FIGS. 5-9. A locking systemis formed at a first and a second edge 4 a, 4 b of a first and secondpanel 1, 1′ for locking the first and the second edge 4 a, 4 b in avertical and/or horizontal direction. Embodiments of the locking systemcomprise a displaceable or compressible tongue that enables assemblingof the first and the second edge 4 a, 4 b by a vertical movement, seeFIGS. 5a-c, 6a-c and 7a-c . Another embodiment, which may comprise afixed tongue, enables assembling of building panels at the adjacentedges by an angular movement, see FIGS. 8a-8c . The locking system ispreferably formed by mechanical cutting, such as milling, drilling,cutting by knife and/or sawing, of the edges of the building panels.

FIG. 5a discloses a tongue 30, which is formed of material of a firstedge of first building panel 1 and at an upper part of the first edge. Atongue groove is formed at a second edge of a second building panel 1′.The tongue 30 is configured to cooperate, in a locked position of thefirst edge and the second edge see FIG. 5c , with the tongue groove 20for vertical locking of the first and the second edge.

A connection part 50 may be formed between outer part of the tongue 30and an upper edge of the first edge. The connection part 50 ispreferably formed by making a groove 51, e.g., by cutting, between theouter part of the tongue 30 and an upper edge of the first edge. Theconnection part keeps the tongue in the correct position before thetongue is displaced.

An insertion groove 40 is formed below the upper part and the tongue 30is displaced into the insertion groove 40, see FIG. 5 b.

The tongue 30 is displaced into the tongue groove 20 during assemblingof the first and the second edge, see FIG. 5c . A contact surface of thetongue is pressed against a contact surface 52 of the tongue groove 20.

An embodiment may have a resilient part (not shown) between the tongue30 and a bottom wall of the insertion groove 40. The resilient partmakes it possible to push the tongue 30 into insertion groove, by anedge of the second edge, during a vertical assembling of the first andthe second edge. The tongue springs back and into the tongue groove whenthe first and the second building panel have reached a locked position.

A locking strip 8 with a vertically protruding locking element 6 isformed at the edge of the first building panel. The locking element 6cooperates with a locking groove 14, formed at the edge of the secondbuilding panel 1′, for horizontal locking of the first and second edge.

Another embodiment is shown in top views in FIGS. 6a-c . The embodimentcomprises an insertion groove 40 with a sidewall 60 formed at a thirdedge, which is adjacent the first edge, of the first building panel 1.An opening of the insertion groove 60 is formed at the forth edge, whichis opposite the third edge and adjacent the first edge, of the firstbuilding panel 1. A pressing part E2 may protrude through the opening ofthe insertion groove. When the first and the second edge are in a lockedposition a force is applied at the pressing part E2. The force pressesan inner part E1 of the tongue 30 against the sidewall 60. The forcebends the tongue 30 and a part of the tongue is pushed into the tonguegroove 20 at the second edge of the second building panel 1′.

Further embodiments are shown in cross sections in FIGS. 7a-c and 8a-c .The tongue 30 and the insertion groove 40 are formed of material of thefirst edge. The width of tongue 30 is greater than the depth of theinsertion groove 40 to obtain a tongue with protruding part thatprotrudes outside the upper edge of the first edge when inserted intothe insertion groove 40. If the edge material is an elastic material,such as plastic or vinyl, the tongue may be compressed, such that theprotruding part is pushed into the insertion groove, and thereby enablea vertical assembling as shown in FIGS. 7b -c.

If the tongue is not compressible and enables a vertical assembling asshown in FIGS. 7b-c , the first and the second edge may be assembled byan angular movement as is shown in 8 a-c. The tongue 30, which may be afixed tongue, which may be arranged firmly in the insertion groove 40,if the first and the second edge are intended to be assembled by anangular movement.

FIGS. 9a-c show a top view of an embodiment of the disclosure in whichan inner groove 90 is formed throughout the tongue 30, between thetongue and the first edge of the building panel, in order to obtain anembodiment of a resilient tongue part. The inner groove extends in thelongitudinal direction of the tongue and between a first and a secondprotruding part 91 of the tongue 30, at the third and the fourth edge ofthe building panel respectively. The resilient tongue part extends fromthe first to the second protruding part. Before the tongue is displacedinto the insertion groove the protruding parts function as connectionparts as described above. A part of the tongue extends outside theinsertion groove when the tongue is displaced into the insertion groove.The second building panel 1′ is provided with recesses 92 in the lowerlip of the tongue groove at positions that correspond to the first andthe second protruding part 60, as is shown in FIG. 9a . The recessenables the second building panel to be assembled to the first buildingpanel by a vertical motion. The resilient part is pushed into theinsertion groove during the vertical motion. When the first and thesecond building panel are in a common horizontal plane, the resilientpart springs back and into the tongue groove and provides for verticallocking of the first and the second building panel. As is shown in FIGS.9b-c , if the insertion groove is provided with the side wall 60 and theopening as described for the embodiment shown in FIG. 6a-c thisembodiment may comprise a further locking step comprising applying aforce at the pressing part E2. The force presses an inner part E1 of thetongue 30 against the sidewall 60. The force bends the tongue 30 and apart of the tongue is pushed into the tongue groove 20 at the secondedge of the second building panel 1′.

The invention claimed is:
 1. Method for producing a locking system atedges of building panels, said locking system comprising a tongue, at afirst edge of a first building panel, cooperating with a tongue groove,at a second edge of an adjacent second building panel, for verticallocking of the building panels, wherein the method comprises the stepsof: forming material of the first edge to obtain at least parts of theouter shape of the tongue in a production line comprising mechanicalcutting devices; forming an insertion groove at the first edge in saidproduction line, wherein said insertion groove is sidewardly open andextends in the horizontal direction; and displacing the tongue in saidproduction line at least partly into the insertion groove.
 2. Method asclaimed in claim 1, wherein parts of the outer shape of the tongue areformed at an upper part of the first edge, above the insertion groove.3. Method as claimed in claim 2, wherein the insertion groove is formedbelow the upper part of the first edge and the tongue is displaceddownwards and into the insertion groove.
 4. Method as claimed in claim1, comprising the step of forming a connection part between the tongueand an upper edge of the first edge.
 5. Method as claimed in claim 4,comprising the step of breaking the connection part by the displacementof the tongue.
 6. Method as claimed in claim 1, comprising the step offorming a connection part by forming a groove between an upper edge ofthe first edge and outer parts of the tongue.
 7. Method as claimed inclaim 1, comprising the step of forming the tongue groove, at the secondedge.
 8. Method as claimed in claim 1, comprising the step of forming asidewall in the insertion groove at a third edge, which is adjacent thefirst edge, and forming an opening of the insertion groove at a fourthedge, which is opposite the third edge and adjacent the first edge. 9.Method as claimed in claim 1, wherein the tongue has essentially thesame length as the length of the first edge.
 10. Method as claimed inclaim 1, comprising the step of forming a locking element at the firstedge and a locking groove at the second edge or a locking element at thesecond edge and a locking groove at the first edge, wherein said lockingelement and locking groove are configured to cooperate for locking ofthe building panels in the horizontal direction.
 11. Method as claimedin claim 1, wherein an inner groove is formed throughout the tongue,between the tongue and the first edge of the building panel, in order toobtain a resilient tongue part.
 12. Method as claimed in claim 11,wherein the inner groove extends in a longitudinal direction of thetongue and between a first protruding part of the tongue and a secondprotruding part of the tongue.
 13. Method as claimed in claim 12,wherein the first protruding part and the second protruding part of thetongue are positioned at a third edge and a fourth edge of the buildingpanel, respectively.
 14. Method as claimed in claim 12, wherein theresilient tongue part extends from the first protruding part to thesecond protruding part.